remove depreciated $.browser

vendor/assets/javascripts/chosen.jquery.coffee

@@ -4,11 +4,15 @@ Copyright (c) 2011 by Harvest
 ###
 root = this
 $ = jQuery
+isIE6or7 = ->
+  msVersion = navigator.userAgent.match(/MSIE ([0-9]{1,}[\.0-9]{0,})/)
+  msie = !!msVersion
+  msie && parseFloat(msVersion[1]) < 8
 
 $.fn.extend({
   chosen: (options) ->
     # Do no harm and return as soon as possible for unsupported browsers, namely IE6 and IE7
-    return this if $.browser.msie and ($.browser.version is "6.0" or  $.browser.version is "7.0")
+    return this if isIE6or7()
     this.each((input_field) ->
       $this = $ this
       $this.data('chosen', new Chosen(this, options)) unless $this.hasClass "chzn-done"